Recently I was playing "Altos Adventure" on mobile.
I was curious how I could implement an effect similar to their game background.
The sprites tint over time to match the time of a day. It's blue in the morning, orange in the evening. Sky color is changing and also mountains tint.
I believe it is possible to change solid color sprite and it seems like mountains have only one color individually. Maybe they use other half transparent sprites to change the tint of the entire scene? Like half transparent curtain. But it doesn't explain the smooth transition between colors during the time.
Any ideas how I can do the same with Unity and Photoshop? I am also interested in mountain fading effect which appears during rain or snowfall.
Screenshots with different tints of background: